list updates to column physics since cice v5.1.2 release

[eclare108213]

Here's what I found, reading through the svn and github logs. Anything else?

• created the column package by refactoring CICE
• added warning package for printing diagnostic and error information from within the column physics
• added vertical biogeochemistry, including particulate iron, humic material, modal aerosols, proteins, stationary and mobile phases
• allow biogeochemistry to feed back on sea ice physics through shortwave formulation

bug fixes:

• use net shortwave sum instead of cosine of the zenith angle to limit shortwave calculation for low-/no-light conditions
• corrected unnecessary roundoff errors in delta Eddington shortwave calculation
• define interface temperature in the brine height parameterization
• provide flexibility for tracking frazil ice salt/water in ice or ocean model
• when ponds are very thin, ignore them in the radiation calculation
• ensure fractions of snow, ponds and bare ice add to 1
• wrap pond tracers in conditional blocks in mushy thermodynamics and form drag parameterization
• miscellaneous bug fixes to bgc, hbrine

[duvivier]

Fixed by pull request #95